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Theories of personal identity have changed over time. Philosophers in the past have focused mainly on the self, whereas modern theorists focus more on personal narratives and narrative identities. One example is Locke's definition of personal identity which states that you are the same person over time if you have personal memories of your past or if you can remember past experiences. Another example is Parfit's rejection of this notion and focus on the importance of psychological continuity, which is when you remain the same even if you are presented with a different physical world or body.


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Throughout history, philosophers have debated the concept of personal identity. Initially, the focus was primarily on the self, but modern theorists are more inclined to study personal narratives and one's narrative identity. According to Locke, a person's memories and their ability to remember past experiences were key to maintaining one's personal identity over time. In contrast, Parfit rejected this view and instead proposed that psychological continuity was the key to remaining the same person. This involves remaining the same individual despite potential changes in the physical world or body.